The short and long-term objective of this proposal is to upgrade and expand the School of Dental Medicine (SDM) Imaging and Analytical Core Facility so that it may continue to operate with state-of-the-art equipment and support the aims of funded investigators who require live cell imaging capabilities. This facility presently houses the only core confocal microscope at the SDM, a 9 year old BioRad Radiance 2000(R). We were recently informed that Zeiss will no longer provide service contracts for these instruments (as of Sept, 2009) and repairs will be made only when and if parts are available. Therefore funds are requested to purchase a live cell confocal imaging (LCCI) system, specifically a Nikon A1R. We chose this single photon high resolution confocal system with hydrid scanning capabilities because it allows for slow and fast scan speeds. In order to provide excitation and detection of fluorophores from the near UV (dapi/hoechst) to the far red (CY5) the system is equipped with a 405nm diode laser, a multiline Argon ion laser, a 638 diode laser and a 561nm solid state laser. The configuration of the system will have 4 PMTS for acquisition of up to 4 colors as well as a 32 channel spectral detector. This configuration was chosen to provide flexibility to meet the diverse needs of our user group. Moreover, it will support our investigators as they expand their studies to larger numbers of fluorochromes and thereby obtain significantly more information per cell. Investigators will be able to monitor: a wide range of both surface and intracellular markers, assess changes in cellular concentrations of ions such as calcium, follow lysosome maturation, analyze viral fusion events and signaling pathways as well as study protein-protein and protein-lipid interactions over time in vivo. Core research facilities are vital to the success of research enterprises such as that at the SDM by providing investigators with access to advanced technologies in their research activities, which, for financial reasons, would otherwise not be affordable to the individual scientist or laboratory. The SDM-IAC supports the diverse needs of over 15 scientists whose research efforts are focused on advancing oral health and understanding basic mechanisms of disease. Supported projects are focused, in particular, on studies on the response of oral and craniofacial tissue to physiologic and pathologic stimuli with emphasis in three areas: inflammation and immunity, infectious disease, and the biology of soft and hard connective tissue.